Synthesis of a New Potential Conjugated TAT-Peptide-Chitosan Nanoparticles Carrier via Disulphide Linkage

Chitosan and TAT peptide have been widely investigated as delivery systems for various biomolecules such as plasmid DNA, oligonucleotides, and siRNAs. Conjugation of chitosan with TAT-peptide was therefore expected to produce a carrier with enhanced ability to facilitate cellular uptake. In this study, chitosan nanoparticles (CNs) were prepared by ionic gelation method prior to conjugation with TAT-peptide via disulphide linkage (CN-TAT). The conjugation was performed at various TAT-peptide-to- chitosan weight ratios ranging from 0.008 : 1 to 0.125 : 1. siRNA as a model biomolecule was loaded by adsorption onto the CN-TAT. Nanosize range particles were produced with a size range of less than 700 nm depending on TAT-peptide concentration used. HPLC and Raman spectrometry analysis revealed that TAT-peptide was successfully conjugated to the CN via disulphide linkage. siRNA loading efficiency for CN-TAT was 93% +/- 0.01. In vitro cytotoxicity studies showed that CN-TAT has relatively low toxicity. In conclusion, TAT conjugated onto CN via disulphide linkage was successfully synthesized, and its low cytoxicity demonstrates a potential for its use as a vector for biomolecules.